Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/005—Control of transmission; Equalising
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
  • H04W52/04—Transmission power control [TPC]
  • H04W52/18—TPC being performed according to specific parameters
  • H04W52/22—TPC being performed according to specific parameters taking into account previous information or commands
  • H04W52/226—TPC being performed according to specific parameters taking into account previous information or commands using past references to control power, e.g. look-up-table
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
  • H04W52/04—Transmission power control [TPC]
  • H04W52/38—TPC being performed in particular situations
  • H04W52/50—TPC being performed in particular situations at the moment of starting communication in a multiple access environment

Definitions

• the present invention relates to a method and an apparatus for the inititation of communication. More specifically, this invention describes the initiation of a connection.
• This initiation is typically started by the Mobile station (also called User Equipment UE) by transmitting an initial signal to the Base station (also called Node B).
• This initial signal can either be a so called RACH (Random Access) message or a preamble only i.e. a specific signal sent prior to a (possible) RACH message transmission.
• RACH Random Access
• preamble only i.e. a specific signal sent prior to a (possible) RACH message transmission.
• power control is a very important issue.
• closed loop power control as used for ordinary data channels cannot be set up in advance. Therefore so called open loop power control is used.
• Layer 1 Before the physical random-access procedure can be initiated, Layer 1 shall receive the following information from the higher layers (RRC):
• Layer 1 shall receive the following information from the higher layers (MAC):
• the physical random-access procedure shall be performed as follows:
• a RACH sub-channel defines a sub-set of the total set of uplink access slots. There are a total of 12 RACH sub-channels.
• the access slots of different RACH sub-channels are also illustrated in Table 7.
• the PRACH contains two sets of access slots as shown in Figure 2.
• L1 shall receive the following information from the higher layers (RRC).
• L1 shall receive the following information from MAC prior to packet transmission:
• the overall CPCH -access procedure consists of two parts:
• the purpose of the present invention is to optimise this procedure, in case the power capability of the UE are exceeded.
• the power with which the UE can transmit any signal is both limited with a maximum power which the UE cannot exceed and a minimum power, which the UE cannot go below. In both cases it could theoretically be possible to transmit with more/less power but then there would be the risk that the transmission quality (e.g. phase accuracy, modulation accuracy, leakage to other channels or other parameters) are compromised. In that case it is still not desirable to exceed the limits.
• the maximum power can also be limited on a cell by cell basis, in order to make sure that no excessive interference is generated in this cell or in surrounding cells.
• the purpose of this invention is to identify a procedure which shows optimal performance not only from the point of view of an individual UE but also form the point of view of the network.
• the next transmission should not be done with the power increment added to the minimum transmission, but with the power increment added to the initial nominal transmission power determined by the open loop power control. If this power increment plus initial nominal transmission power determined by the open loop power control is still below the minimum transmission power of the UE, then again the latter must be used.
• the power ramping is not started from the actually used transmission power of the previous transmission but from the power which would have been used for the previous transmission in case no constraint regarding a minimum UE transmission power had existed and then possibly this constraint is taken into account, after calculating the ideal next transmission power.
• transmission attempts at the same power are only performed for a given maximum number of attempts, here called Nmin, afterwards a power increment is performed based on the last used power.
• Nmin a power increment is performed based on the last used power.
• the UE will continue to transmit transmission attempts at the maximum power, typically until a predetermined maximum number of transmission attempts (Nmax) is exceeded.
• Nmax a predetermined number
• the transmission is stopped if more than a predetermined number of transmission attempts have been performed.
• the transmission is stopped if the nominal power (i.e. power with which the transmission would be sent in case the constraint of maximum UE power had not been taken into account) is limited by a predetermined value (Pmax) and the transmission is stopped if this value would be exceeded.
• Pmax a predetermined value
• the power of any further transmission after this initial transmission could not be based on the open loop estimate but on the power of the last acknowledged transmission. Because the latter has obviously been received successfully by the base station, it generally provides a better power estimate than the open loop estimate. This is also true if the transmission power was limited by the above mentioned procedures.
• the high data rate communication needs 10 dB more power than the initial RACH transmission (typically the RACH preamble transmission)

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Mobile Radio Communication Systems (AREA)
• Transmitters (AREA)

Priority Applications (12)

Applications Claiming Priority (1)

Publications (1)

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ID=8170047

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Family Applications After (2)

Country Status (9)

Cited By (11)

Families Citing this family (13)

Citations (2)

Family Cites Families (4)

• 2000
  • 2000-10-10 EP EP00122013A patent/EP1198076A1/fr not_active Withdrawn
• 2001
  • 2001-10-05 JP JP2002535288A patent/JP4021761B2/ja not_active Expired - Lifetime
  • 2001-10-05 CN CN2009100067405A patent/CN101488789B/zh not_active Expired - Lifetime
  • 2001-10-05 AU AU2001295594A patent/AU2001295594A1/en not_active Abandoned
  • 2001-10-05 DE DE50114550T patent/DE50114550D1/de not_active Expired - Lifetime
  • 2001-10-05 ES ES01976275T patent/ES2315310T3/es not_active Expired - Lifetime
  • 2001-10-05 EP EP01976275A patent/EP1325565B1/fr not_active Expired - Lifetime
  • 2001-10-05 US US10/399,155 patent/US7130652B2/en not_active Expired - Lifetime
  • 2001-10-05 CN CNB018139507A patent/CN100477550C/zh not_active Expired - Lifetime
  • 2001-10-05 WO PCT/EP2001/011530 patent/WO2002032010A1/fr not_active Ceased
  • 2001-10-05 KR KR1020037004999A patent/KR100815636B1/ko not_active Expired - Lifetime
  • 2001-10-05 EP EP08014163.3A patent/EP1983658B1/fr not_active Expired - Lifetime

Patent Citations (2)

Non-Patent Citations (1)

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